Hmm, it was noted that Feanor wedded Nerdanel while he was still in early youth, and I get the
impression at least (I haven't really looked at all the relevant texts here) that possibly he was married before Galadriel was born.
Anyway, according to later texts Feanor wondered at Galadriel's hair... but many likely did
As an artist of such amazing calibre, Feanor's asking for Nerwenian hair might be due to his fiery, creative zeal. At least that's how I thought of it.